2,7-Naphthalenedisulfonic acid, 4-amino-5-hydroxy-3-((3-nitrophenyl)azo)-6-(phenylazo)-, disodium salt 5850-35-1 Disodium 4-amino-5-hydroxy-3-((3-nitrophenyl)azo)-6-(phenylazo)naphthalene-2,7-disulphonate EINECS 227-449-7